An aluminum lockring tool for a pinion drive bicycle gearbox is a tool used to remove or install the lockring that holds the cogset in place on bicycles equipped with a pinion drive gearbox. The tool is designed to fit over the lockring a It is made of aluminum and steel. To use the tool, you simply place it over the lockring and turn it counterclockwise to loosen the lockring, or clockwise to tighten it.
